Rotating vane pump



A ril 25, 1967 P. SALMINEN 3,315,610

ROTATING VANE PUMP Filed June 29, 1965 3 Sheets-Sheet 1 April 1967 P. SALMINEN ROTATING VANE PUMP 3 Sheets-Sheet 3 Filed June 29, 1965 FIG. 5

United States Patent 3,315,610 ROTATING VANE PUMP Paavo Salminen, Topeliusgatan 3BA17, Helsingfors, Finland Filed June 29, 1965, Ser. No. 467,863 Claims priority, application Finland, Sept. 29, 1964, 2,055/ 64; Mar. 15, 1965, 630/65 6 Claims. (Cl. 103-139) by a partition wall.

In rotating vane pumps of the above described kind, rotation of the rotor causes the vanes also to rotate, the vanes thus carrying fluid from the pump inlet to the pump outlet. The partition wall is provided with inclined flank portions adjacent the pump inlet and the pump outlet, said inclined flank portions serving to lift each approaching vane up an inclined flank.

onto the fiat top surface of the partition wall, and to gradually lower a vane after it has passed over the partition wall. Thus, fluid is pumped out through the outlet passage by the co-operation of one vane on top of a partition wall, the rotor, the partition wall itself, and the vane immediately approaching the partition wall.

However, one disadvantage of a pump of the above described kind, is that as a vane slides up an inclined flank the pumped medium, as well as being forced out through the outlet, is also forced through the gap between the top of the vane and the rotor with a progressively increasing speed. This leads to noisy operation of the pump and also to a loss of efiiciency.

The present invention has for its object to eliminate or at least reduce the above stated disadvantages.

According to the present invention therefore, there is provided a vane pump comprising a pump body, a rotor mounted for rotation within said pump body, slots being provided in said rotor for receiving vanes slidably mounted therewithin, a portion of said vanes normally lying within a pump chamber, adapted to contain the fluid to be pumped, said vanes serving to move the fluid from a fluid inlet towards a fluid outlet communicating with said chamber, a partition wall being provided which serves to separate said fluid inlet from said fluid outlet, wherein each vane is provided with guide means associated with a side edge portion thereof, said :guide means co-operating with cam means, such that movement of the vanes with respect to said cam means causes such vanes to be guided over the partition wall.

By departing from the conventional guiding of the vanes by their axial end regions and disposing guide members of the vanes on a portion thereof which is located between its axial end portions, the partition wall between the inlet and outlet in the pump chamber can be formed without any inclined flanks.

Also the forcing of fluid over the top of a vane and -the consequent noise and loss of efficiency is avoided.

The axial displacement of a vane out from the pump chamber as it passes over the partition wall is carried out by co-operation between guide members provided on each vane and said cam means. A vane is wholly withdrawn from the pump chamber and completely drawn inside the rotor just prior to reaching the partition wall.

If the guide members are situated on the side of each vane facing the central axis of the rotor, their speeds will be relatively low as they rotate and thus reduce wear.

3,3 15,6 l0 Patented Apr. 25, 1 967 In order that the invention maybe more readily understood, one embodiment of pump will now be described by way of example and with reference to the accompanying drawings, in which FIGURE 1 shows an axial section of a preferred embodiment of a rotating vane pump according to the invention,

FIGURE 2 shows a section of the pump of FIGURE 1 along the line IIH in FIGURE 1,

FIGURE 3 shows a perspective view of a detail of the pump of FIGURES 1 and 2,

FIGURE 4 shows another embodiment of a vane,

FIGURE 5 shows a third embodiment of a vane as seen from the side and FIGURE 6 shows the vane of FIGURE 5 as a section along the line VIVI in FIGURE 5.

The rotating vane pump shown in FIGURES 1 to 3 consists of a cylindrical pump body 1, in which there is, by means of bearings 2, rotatably mounted a rotor 3. The rotor is provided with six slots 4 equally spaced around the central axis of the rotor. In each slot 4 there is arranged, with a small clearance, an axially movable vane 5. The pump body is closed by an end Wall 6 which is provided with a central plug 7 which fits with a small clearance in the rotor 3. Between the end wall 6 and the rotor 3 there is formed an annular pump chamber 8 which is concentric with the rotor. The pump chamber 8 is provided with, an inlet 9 and an outlet 10, formed in the end wall 6, for the fluid to be pumped. The pump chamber is provided with a partition wall 11 between the inlet 9 and the outlet 10 which prevents the inlet and the outlet from communicating with another over the partition wall.

Each vane 5 is provided between its axial ends with a rotatably mounted guide roller 12, which is arranged on that side of the vane which faces the center axis of the rotor. In the central plug 7, there is formed a peripheral groove 13, with which the rollers 12 cooperate to produce axial displacement of the vanes while the rotor rotates.

As shown in FIGURE 3 the groove 13 is formed above the partition Wall 11 with a camlike profile 14, slanting surfaces 15 and 16 being provided thereon. By forming the groove 13 in this way the vanes, during their passage from the inlet 9 to the outlet 10 remain in a position projecting into the pump chamber; and during their passage from the outlet to the inlet they will be forced by the elevation of the cam-like groove out of the pump chamber and into the rotor 3, so that the vanes can pass over the partition wall. The portions 14, 15 of the groove are arranged so that each vane is wholly drawn into the rotor before reaching the partition wall whereby compression of the medium transported by the vane from 'the pump chamber inlet 9 to the outlet 10 is prevented as the vane lifts to pass over the partition wall.

When the vane pump is working as a pressure pump, the rotor may be provided with a channel 17 in front of each slot 4 with respect to the direction of rotation of the rotor. The channel 17 serves to connect a slot 4 with the pump chamber. In this way the pumped fluid acts with the same pressure on both axial end surfaces of each vane, whereby the vanes are balanced.

The rollers 12 of the vanes are, therefore, substantially loaded only while the vanes are shifted axially by the slanting portions 15 and 16 out from the pump chamber and back again into the pump chamber.

When the pump works as a vacuum pump, the balancing of the vanes may be obtained by connecting the bottom part of the slots 4 with one another, for example by removing the packing 18 in the construction according to FIGURE 1. By making the bottom part of the slots com- 'shows such an embodiment.

municate with one another in this way a balance of pressure is obtained.

The above described balancing of the vanes may also be obtained without the channels 17,.by providing'the advantages.

In the case where the channels are made in the rotor itself, (channels 17 in FIGS. 1-3) the performance of the rotor will be limited to a single direct-ion of rotation, depending on which side of each slot the channel is positioned, because the channels must be arranged in front of each slot with respect to the direction of rotation of the with two axial channels 19 rotor. By forming the channels'in the vanes instead of in the rotor, the same rotor construction can be used for left hand rotation as well as for right hand rotation, in which case the differences between pumps rotating in I opposite directions can be'limited to the form of the vanes.

By forming the channels in thevanes, it is possible to form the vanes from a plastic material, since the suction which no'rmally'appears in large'plastic bodies, can be effectively avoided by making the vanes of a hollow construction with relatively thin but still sufficiently strong walls.

According to the embodiment of the pump illustrated 13. In such a construction, the roller running in the groove receives the axial forces which are transmitted to the vane.

However, it has been proved in practice that pumps used for heavier working performance should have the guide member and the guide groove constructed so that the guide member also can receive the radially inward directed forces acting upon the vane, which are caused by the pumped fluid. By means of such a construction, the contact pressure of the vane against the center plug can be reduced and thus also the wear of the vane will be re-- duced. FIGURES Sand 6 illustrate such an embodiment.

A ball 24 is mounted in a substantially semi-spherical pivot seat 25 in the vane 23 on that side of the vane which faces the center axis of the'rotor. The peripheral guide groove inthe center plug projecting into the rotor is in this case of a substantially semi-circular cross-section, so that the ball, lbesides receiving the axial guide forces mentioned in connection with FIGURES 1-3 also receives radial guide forces as shown schematically by in FIGURES 14, the guide members of the vanes 5, 18 consist of rollers 12 which run in the peripheral groove dash-lines in FIGURE 5. The depth of the seat with I respect to the diameter of the ball, is adjusted so that the volume of the bearing seat is less than" half of the volume of the ball, i.e. the center of the ball is situated outside the side plane 23- of the vane. By this arrangement the rolling of the ball in the guide groove in the center plug takes place along the great circle of the ball,

. whereby the forces between the ball and the groove walls are directed through the center of the ball,

The vane 23 is further provided in the manner shown 7 in FIGURE 4 with two axially extending open channels 26, for the balancing ofthe vane in the above described 7 way. The semi-spherical bearing seat 25 is, by meansof a bore 27, connected with the channel 26and thus isalso 7 a connected with the pump chamber. By this means a floating bearing for the 'ball in the seat formed in the vane' is obtained, so that wear of the ball and' its respective seat is reduced to a minimum.

What I claim is:

1. A vane pump comprising a pump body, a rotor mounted for rotation within said pump body, said'rotor having slots arranged therein, vanes mounted within said slots for axial sliding movement therein, said rotor and pump body defining a pump chamber adapted to contain the fluid to be pumped, said pump body having an inlet and an outlet in communication with said chamber for' the passage of fluid to and from said chamber, a portion of said vanes normally lying within said pump chamber,

said vanes serving'to move the fluid from said fluid inlet towards said fluid outlet, a partition wall in said chamber for separating said fluid inlet and said fluid outlet, fsaid pump body including a stationary central axially .pro-i I truding plug portion within said rotor, each vane having an inner side edge portion facing said plug portion, guide means on each vane at said inner side edge portion thereof,

and cam means on said plug portion cooperating .With 7 said guide means such that movement of the vanes with respect to said cam means causes said vanes tobe guided over the partition wall.

2. A vane pump as claimed in claim 1, wherein said cam means is constitutedby a peripheral guide 'groovein said plug.

3. A vane pump as claimed in claim '2, whereinsaid guide means comprises a guide roller associated'with each vane, each said roller being received in said groove which is shaped such that relative rotary movement of the vanes about the longitudinal axis of the plug causes said vanes to move axially with respect to said plug,

4. A vane pump as claimed in claim 2,.wherein said guide means comprises a ball received in a substantially semi-spherical bearing seat in each vane, each said \ball being received in said groove which is shaped such that relative rotary movement of the vanes about the longitudinal axis of the plug causes said vanes to move axially with respect to said plug, said ball serving to transmit both axial and radial forces to the vane.

5. A vane pump as claimed in claim 4,'wherein at v least one vane is provided with'a bore which connects the bearing seat for the said ball with the pump1chamber. 6. A vane pump as claimed in claim 4, wherein the volume of the bearing seat is less than half of the volume of the ball.

References Cited bythe Examiner V UNITED STATES PATENTS 1,028,285 6/1912 Sadger 91126 7 1,042,696 10/1912 Lehne 103-439 1,175,153 3/1916 Klinger 103-139 2,401,376 6/1946 Sherman 91-126 3,163,090 12/ 1964 Conrad 91-126 DONLEY I. STOCKING, Primary Examiner MARK NEWMAN, Examiner. M. VARGO, w. 1, (300mm, Assistant Examiners. 

1. A VANE PUMP COMPRISING A PUMP BODY, A ROTOR MOUNTED FOR ROTATION WITHIN SAID PUMP BODY, SAID ROTOR HAVING SLOTS ARRANGED THEREIN, VANES MOUNTED WITHIN SAID SLOTS FOR AXIAL SLIDING MOVEMENT THEREIN, SAID ROTOR AND PUMP BODY DEFINING A PUMP CHAMBER ADAPTED TO CONTAIN THE FLUID TO BE PUMPED, SAID PUMP BODY HAVING AN INLET AND AN OUTLET IN COMMUNICATION WITH SAID CHAMBER FOR THE PASSAGE OF FLUID TO AND FROM SAID CHAMBER, A PORTION OF SAID VANES NORMALLY LYING WITHIN SAID PUMP CHAMBER, SAID VANES SERVING TO MOVE THE FLUID FROM SAID FLUID INLET TOWARDS SAID FLUID OUTLET, A PARTITION WALL IN SAID CHAMBER FOR SEPARATING SAID FLUID INLET AND SAID FLUID OUTLET, SAID PUMP BODY INCLUDING A STATIONARY CENTRAL AXIALLY PROTRUDING PLUG PORTION WITHIN SAID ROTOR, EACH VANE HAVING AN INNER SIDE EDGE PORTION FACING SAID PLUG PORTION, GUIDE MEANS ON EACH VANE AT SAID INNER SIDE EDGE PORTION THEREOF, AND CAM MEANS ON SAID PLUG PORTION COOPERATING WITH SAID GUIDE MEANS SUCH THAT MOVEMENT OF THE VANES WITH RESPECT TO SAID CAM MEANS CAUSES SAID VANES TO BE GUIDED OVER THE PARTITION WALL. 